<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title></title>
	<script src="js/vue.js"></script>
	</head>
	<body>
		<div id="app">
		<div v-if="isShow" ref="self">
			test
		</div>
		<button @click="isShow=!isShow">更新</button>
		    </div>
		<script>
			var vm = new Vue({
				el:'#app',
				data:{
					isShow:false
				},
				beforeUpdate(){
					console.log('更新之前')
					console.log(this.$refs.self)
				},
				updated(){
					console.log('更新之后')
					console.log(this.$refs.self)
				}
			})
		</script>
	</body>
</html>
